Add test cases for HTML5 number input step attribute

The step attribute determines what values should be accepted by an HTML5
number input. If set to "any" or a floating point value, floating point
values should be permitted for the input by the validator.
Use `number` constraint for HTML5 number input if non-int step attribute

HTML5 number inputs allow floating-point numbers if the "step" attribute
is set to "any" or a floating-point number. In this case the appropriate
Parsley constraint would be "number".
Added test for html5 attributes minlength and maxlength
Added parsing of html5 attributes minlength and maxlength
Merge pull request #731 from maniacyak/HTML5-number-validation-fix

Use number constraint for HTML5 number inputs if an appropriate 'step' attribute is set
Add missing doc for 'parsley:field:validated' event
Add new 'parsley:form:error' and 'validated' events
Merge pull request #783 from marcandre/validated_with_result

Validated with result
Fix obviously wrong conditional
Remove needless parameters.
Better not give the impression the function isn't bound to outer scope (or else make it independent and add the argument  `requirements` too)
Store created assert and reuse.
This makes it clearer when asserts need to be created and is more efficient.
Merge pull request #784 from marcandre/constraints_modifs

Constraints modifs
Modify comparisons in extra to accept direct numbers [#785]
Let's not pollute
Be explicit
Merge pull request #786 from marcandre/strict_comparisons

Modify comparisons in extra to accept direct numbers [#785]
Merge pull request #787 from marcandre/green

Green
Fix event emitted. See [#783]
Merge pull request #788 from marcandre/fix_form_events

Fix event emitted. See [#783]
fix luhn validator and formatting